A new statewide report card asks a simple question: are Pennsylvania’s rivers and lakes safe for swimming? For more than half of the places tested, the answer at least some of the time was no.
PennEnvironment’s report, Are Pennsylvania’s Rivers and Lakes Safe for Swimming?, found 55 percent of 653 monitoring sites statewide tested positive for unsafe E. coli levels at least once, and nearly 40 percent were unsafe on at least a quarter of testing days. Pittsburgh’s Saw Mill Run and the Monongahela were among the flagged waters.
What the testing found
The report, released August 24, compiles bacteria monitoring from across the state and compares it to the EPA’s Beach Action Value, the threshold health agencies use to decide when water is unsafe for swimmers. Fecal contamination at those levels can cause gastrointestinal illness and skin infections for the growing number of people paddling, wading, and swimming in our rivers.
The local picture
Southwestern Pennsylvania features prominently. Saw Mill Run, the stream that drains a big slice of Pittsburgh’s South Hills, showed unsafe fecal bacteria in nearly 90 percent of samples, and the Monongahela through Pittsburgh was highlighted among problem stretches. The culprit is familiar: aging sewer systems that overflow when it rains, plus failing septic systems and agricultural runoff further upstream.
“We ought to have access to clean, healthy water when we visit our great waterways in any part of Pennsylvania.”
David Masur, executive director, PennEnvironment
Why it matters for the rest of us
River recreation is the front door through which most people come to care about water. This report is useful ammunition for the case that sewer and septic investment is not an abstraction: EPA estimates put the need at hundreds of millions of dollars a year for decades, far beyond current funding. If your group does bacteria monitoring, this is also a moment to share your data, since the statewide picture is only as good as the local monitoring behind it.
Source: Pennsylvania Capital-Star, reporting by Ian Karbal on the PennEnvironment Research and Policy Center report, August 24, 2026. Current as of September 11, 2026.
